/* $OpenBSD: session.c,v 1.174 2004/06/09 13:01:44 henning Exp $ */ /* * Copyright (c) 2003, 2004 Henning Brauer * * Permission to use, copy, modify, and distribute this software for any * purpose with or without fee is hereby granted, provided that the above * copyright notice and this permission notice appear in all copies. * * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "bgpd.h" #include "mrt.h" #include "session.h" #define PFD_PIPE_MAIN 0 #define PFD_PIPE_ROUTE 1 #define PFD_SOCK_CTL 2 #define PFD_LISTENERS_START 3 void session_sighdlr(int); int setup_listeners(u_int *); void init_conf(struct bgpd_config *); void init_peer(struct peer *); int timer_due(time_t); void start_timer_holdtime(struct peer *); void start_timer_keepalive(struct peer *); void session_close_connection(struct peer *); void change_state(struct peer *, enum session_state, enum session_events); int session_setup_socket(struct peer *); void session_accept(int); int session_connect(struct peer *); void session_tcp_established(struct peer *); void session_open(struct peer *); void session_keepalive(struct peer *); void session_update(u_int32_t, void *, size_t); void session_notification(struct peer *, u_int8_t, u_int8_t, void *, ssize_t); int session_dispatch_msg(struct pollfd *, struct peer *); int parse_header(struct peer *, u_char *, u_int16_t *, u_int8_t *); int parse_open(struct peer *); int parse_update(struct peer *); int parse_refresh(struct peer *); int parse_notification(struct peer *); int parse_keepalive(struct peer *); int parse_capabilities(struct peer *, u_char *, u_int16_t); void session_dispatch_imsg(struct imsgbuf *, int, u_int *); void session_up(struct peer *); void session_down(struct peer *); int la_cmp(struct listen_addr *, struct listen_addr *); struct peer *getpeerbyip(struct sockaddr *); int session_match_mask(struct peer *, struct sockaddr *); struct peer *getpeerbyid(u_int32_t); static struct sockaddr *addr2sa(struct bgpd_addr *, u_int16_t); struct bgpd_config *conf, *nconf = NULL; struct bgpd_sysdep sysdep; struct peer *npeers; volatile sig_atomic_t session_quit = 0; int pending_reconf = 0; int csock = -1; struct imsgbuf ibuf_rde; struct imsgbuf ibuf_main; struct mrt_config_head mrt_l; void session_sighdlr(int sig) { switch (sig) { case SIGINT: case SIGTERM: session_quit = 1; break; } } int setup_listeners(u_int *la_cnt) { int opt; struct listen_addr *la; u_int cnt = 0; if (TAILQ_EMPTY(conf->listen_addrs)) { if ((la = calloc(1, sizeof(struct listen_addr))) == NULL) fatal("setup_listeners calloc"); la->fd = -1; la->flags = DEFAULT_LISTENER; la->sa.ss_len = sizeof(struct sockaddr_in); ((struct sockaddr_in *)&la->sa)->sin_family = AF_INET; ((struct sockaddr_in *)&la->sa)->sin_addr.s_addr = htonl(INADDR_ANY); ((struct sockaddr_in *)&la->sa)->sin_port = htons(BGP_PORT); TAILQ_INSERT_TAIL(conf->listen_addrs, la, entry); if ((la = calloc(1, sizeof(struct listen_addr))) == NULL) fatal("setup_listeners calloc"); la->fd = -1; la->flags = DEFAULT_LISTENER; la->sa.ss_len = sizeof(struct sockaddr_in6); ((struct sockaddr_in6 *)&la->sa)->sin6_family = AF_INET6; ((struct sockaddr_in6 *)&la->sa)->sin6_port = htons(BGP_PORT); TAILQ_INSERT_TAIL(conf->listen_addrs, la, entry); } TAILQ_FOREACH(la, conf->listen_addrs, entry) { la->reconf = RECONF_NONE; cnt++; if (la->fd != -1) continue; if ((la->fd = socket(la->sa.ss_family, SOCK_STREAM, IPPROTO_TCP)) == -1) fatal("socket"); opt = 1; if (setsockopt(la->fd, IPPROTO_TCP, TCP_MD5SIG, &opt, sizeof(opt)) == -1) { if (errno == ENOPROTOOPT) { /* system w/o md5sig */ log_warnx("md5sig not available, disabling"); sysdep.no_md5sig = 1; } else fatal("setsockopt TCP_MD5SIG"); } if (bind(la->fd, (struct sockaddr *)&la->sa, la->sa.ss_len) == -1) { if (errno == EACCES) { log_warnx("can't establish listener on %s", log_sockaddr((struct sockaddr *)&la->sa)); close(la->fd); la->fd = -1; return (-1); } else fatal("bind"); } session_socket_blockmode(la->fd, BM_NONBLOCK); if (listen(la->fd, MAX_BACKLOG)) { close(la->fd); fatal("listen"); } log_info("listening on %s", log_sockaddr((struct sockaddr *)&la->sa)); } *la_cnt = cnt; return (0); } int session_main(struct bgpd_config *config, struct peer *cpeers, struct network_head *net_l, struct filter_head *rules, struct mrt_head *m_l, int pipe_m2s[2], int pipe_s2r[2]) { int nfds, i, j, timeout, idx_peers, idx_listeners; pid_t pid; time_t nextaction; u_int pfd_elms = 0, peer_l_elms = 0, new_cnt; u_int listener_cnt, peer_cnt, ctl_cnt; struct passwd *pw; struct peer *p, **peer_l = NULL, *last, *next; struct network *net; struct mrt *m; struct mrt_config *mrt; struct filter_rule *r; struct pollfd *pfd = NULL; struct ctl_conn *ctl_conn; struct listen_addr *la; void *newp; short events; conf = config; peers = cpeers; switch (pid = fork()) { case -1: fatal("cannot fork"); case 0: break; default: return (pid); } /* control socket is outside chroot */ if ((csock = control_init()) == -1) fatalx("control socket setup failed"); if ((pw = getpwnam(BGPD_USER)) == NULL) fatal(NULL); if (chroot(pw->pw_dir) == -1) fatal("chroot"); if (chdir("/") == -1) fatal("chdir(\"/\")"); setproctitle("session engine"); bgpd_process = PROC_SE; listener_cnt = 0; setup_listeners(&listener_cnt); if (pfkey_init(&sysdep) == -1) fatalx("pfkey setup failed"); if (setgroups(1, &pw->pw_gid) || setegid(pw->pw_gid) || setgid(pw->pw_gid) || seteuid(pw->pw_uid) || setuid(pw->pw_uid)) fatal("can't drop privileges"); endpwent(); signal(SIGTERM, session_sighdlr); signal(SIGINT, session_sighdlr); signal(SIGPIPE, SIG_IGN); log_info("session engine ready"); close(pipe_m2s[0]); close(pipe_s2r[1]); init_conf(conf); imsg_init(&ibuf_rde, pipe_s2r[0]); imsg_init(&ibuf_main, pipe_m2s[1]); TAILQ_INIT(&ctl_conns); csock = control_listen(); LIST_INIT(&mrt_l); peer_cnt = 0; ctl_cnt = 0; /* filter rules are not used in the SE */ while ((r = TAILQ_FIRST(rules)) != NULL) { TAILQ_REMOVE(rules, r, entries); free(r); } free(rules); /* network list is not used in the SE */ while ((net = TAILQ_FIRST(net_l)) != NULL) { TAILQ_REMOVE(net_l, net, network_l); free(net); } /* main mrt list is not used in the SE */ while ((m = LIST_FIRST(m_l)) != NULL) { LIST_REMOVE(m, list); free(m); } while (session_quit == 0) { /* check for peers to be initialized or deleted */ last = NULL; for (p = peers; p != NULL; p = next) { next = p->next; if (!pending_reconf) { /* new peer that needs init? */ if (p->state == STATE_NONE) { init_peer(p); peer_cnt++; } /* reinit due? */ if (p->conf.reconf_action == RECONF_REINIT) { bgp_fsm(p, EVNT_STOP); p->IdleHoldTimer = time(NULL); } /* deletion due? */ if (p->conf.reconf_action == RECONF_DELETE) { bgp_fsm(p, EVNT_STOP); log_peer_warnx(&p->conf, "removed"); if (last != NULL) last->next = next; else peers = next; free(p); peer_cnt--; continue; } p->conf.reconf_action = RECONF_NONE; } last = p; } if (peer_cnt > peer_l_elms || peer_cnt + PEER_L_RESERVE < peer_l_elms) { if ((newp = realloc(peer_l, sizeof(struct peer *) * peer_cnt + PEER_L_RESERVE)) == NULL) { /* panic for now */ log_warn("could not resize peer_l from %u -> %u" " entries", peer_l_elms, peer_cnt + PEER_L_RESERVE); fatalx("exiting"); } peer_l = newp; peer_l_elms = peer_cnt + PEER_L_RESERVE; } new_cnt = PFD_LISTENERS_START + listener_cnt + peer_cnt + ctl_cnt; if (new_cnt > pfd_elms || new_cnt + PFD_RESERVE < pfd_elms) { if ((newp = realloc(pfd, sizeof(struct pollfd) * (new_cnt + PFD_RESERVE))) == NULL) { /* panic for now */ log_warn("could not resize pfd from %u -> %u" " entries", pfd_elms, new_cnt + PFD_RESERVE); fatalx("exiting"); } pfd = newp; pfd_elms = new_cnt + PFD_RESERVE; } bzero(pfd, sizeof(struct pollfd) * pfd_elms); pfd[PFD_PIPE_MAIN].fd = ibuf_main.fd; pfd[PFD_PIPE_MAIN].events = POLLIN; if (ibuf_main.w.queued > 0) pfd[PFD_PIPE_MAIN].events |= POLLOUT; pfd[PFD_PIPE_ROUTE].fd = ibuf_rde.fd; pfd[PFD_PIPE_ROUTE].events = POLLIN; if (ibuf_rde.w.queued > 0) pfd[PFD_PIPE_ROUTE].events |= POLLOUT; pfd[PFD_SOCK_CTL].fd = csock; pfd[PFD_SOCK_CTL].events = POLLIN; nextaction = time(NULL) + 240; /* loop every 240s at least */ i = PFD_LISTENERS_START; TAILQ_FOREACH(la, conf->listen_addrs, entry) { pfd[i].fd = la->fd; pfd[i].events = POLLIN; i++; } idx_listeners = i; for (p = peers; p != NULL; p = p->next) { /* check timers */ if (timer_due(p->HoldTimer)) bgp_fsm(p, EVNT_TIMER_HOLDTIME); if (timer_due(p->ConnectRetryTimer)) bgp_fsm(p, EVNT_TIMER_CONNRETRY); if (timer_due(p->KeepaliveTimer)) bgp_fsm(p, EVNT_TIMER_KEEPALIVE); if (timer_due(p->IdleHoldTimer)) bgp_fsm(p, EVNT_START); if (timer_due(p->IdleHoldResetTimer)) { p->IdleHoldTime /= 2; if (p->IdleHoldTime <= INTERVAL_IDLE_HOLD_INITIAL) { p->IdleHoldTime = INTERVAL_IDLE_HOLD_INITIAL; p->IdleHoldResetTimer = 0; } else p->IdleHoldResetTimer = time(NULL) + p->IdleHoldTime; } /* set nextaction to the first expiring timer */ if (p->ConnectRetryTimer && p->ConnectRetryTimer < nextaction) nextaction = p->ConnectRetryTimer; if (p->HoldTimer && p->HoldTimer < nextaction) nextaction = p->HoldTimer; if (p->KeepaliveTimer && p->KeepaliveTimer < nextaction) nextaction = p->KeepaliveTimer; if (p->IdleHoldTimer && p->IdleHoldTimer < nextaction) nextaction = p->IdleHoldTimer; if (p->IdleHoldResetTimer && p->IdleHoldResetTimer < nextaction) nextaction = p->IdleHoldResetTimer; /* are we waiting for a write? */ events = POLLIN; if (p->wbuf.queued > 0 || p->state == STATE_CONNECT) events |= POLLOUT; /* poll events */ if (p->fd != -1 && events != 0) { pfd[i].fd = p->fd; pfd[i].events = events; peer_l[i - idx_listeners] = p; i++; } } idx_peers = i; TAILQ_FOREACH(ctl_conn, &ctl_conns, entries) { pfd[i].fd = ctl_conn->ibuf.fd; pfd[i].events = POLLIN; if (ctl_conn->ibuf.w.queued > 0) pfd[i].events |= POLLOUT; i++; } timeout = nextaction - time(NULL); if (timeout < 0) timeout = 0; if ((nfds = poll(pfd, i, timeout * 1000)) == -1) if (errno != EINTR) fatal("poll error"); if (nfds > 0 && pfd[PFD_PIPE_MAIN].revents & POLLOUT) if (msgbuf_write(&ibuf_main.w) < 0) fatal("pipe write error"); if (nfds > 0 && pfd[PFD_PIPE_MAIN].revents & POLLIN) { nfds--; session_dispatch_imsg(&ibuf_main, PFD_PIPE_MAIN, &listener_cnt); } if (nfds > 0 && pfd[PFD_PIPE_ROUTE].revents & POLLOUT) if (msgbuf_write(&ibuf_rde.w) < 0) fatal("pipe write error"); if (nfds > 0 && pfd[PFD_PIPE_ROUTE].revents & POLLIN) { nfds--; session_dispatch_imsg(&ibuf_rde, PFD_PIPE_ROUTE, &listener_cnt); } if (nfds > 0 && pfd[PFD_SOCK_CTL].revents & POLLIN) { nfds--; ctl_cnt += control_accept(csock); } for (j = PFD_LISTENERS_START; nfds > 0 && j < idx_listeners; j++) if (pfd[j].revents & POLLIN) { nfds--; session_accept(pfd[j].fd); } for (; nfds > 0 && j < idx_peers; j++) nfds -= session_dispatch_msg(&pfd[j], peer_l[j - idx_listeners]); for (; nfds > 0 && j < i; j++) nfds -= control_dispatch_msg(&pfd[j], &ctl_cnt); } while ((p = peers) != NULL) { peers = p->next; bgp_fsm(p, EVNT_STOP); pfkey_remove(p); free(p); } while ((mrt = LIST_FIRST(&mrt_l)) != NULL) { LIST_REMOVE(mrt, list); free(mrt); } while ((la = TAILQ_FIRST(conf->listen_addrs)) != NULL) { TAILQ_REMOVE(conf->listen_addrs, la, entry); free(la); } free(conf->listen_addrs); msgbuf_write(&ibuf_rde.w); msgbuf_clear(&ibuf_rde.w); msgbuf_write(&ibuf_main.w); msgbuf_clear(&ibuf_main.w); control_shutdown(); log_info("session engine exiting"); _exit(0); } void init_conf(struct bgpd_config *c) { if (!c->holdtime) c->holdtime = INTERVAL_HOLD; } void init_peer(struct peer *p) { p->fd = p->wbuf.fd = -1; p->capa.announce = p->conf.capabilities; p->capa.ann_mp = 1; p->capa.ann_refresh = 1; change_state(p, STATE_IDLE, EVNT_NONE); p->IdleHoldTimer = time(NULL); /* start ASAP */ } void bgp_fsm(struct peer *peer, enum session_events event) { switch (peer->state) { case STATE_NONE: /* nothing */ break; case STATE_IDLE: switch (event) { case EVNT_START: peer->HoldTimer = 0; peer->KeepaliveTimer = 0; peer->IdleHoldTimer = 0; /* allocate read buffer */ peer->rbuf = calloc(1, sizeof(struct buf_read)); if (peer->rbuf == NULL) fatal(NULL); peer->rbuf->wpos = 0; /* init write buffer */ msgbuf_init(&peer->wbuf); /* init pfkey - remove old if any, load new ones */ pfkey_remove(peer); if (pfkey_establish(peer) == -1) { log_peer_warnx(&peer->conf, "pfkey setup failed"); return; } if (peer->conf.passive || peer->conf.template) { change_state(peer, STATE_ACTIVE, event); peer->ConnectRetryTimer = 0; } else { change_state(peer, STATE_CONNECT, event); session_connect(peer); peer->ConnectRetryTimer = time(NULL) + INTERVAL_CONNECTRETRY; } break; default: /* ignore */ break; } break; case STATE_CONNECT: switch (event) { case EVNT_START: /* ignore */ break; case EVNT_CON_OPEN: session_tcp_established(peer); session_open(peer); peer->ConnectRetryTimer = 0; change_state(peer, STATE_OPENSENT, event); break; case EVNT_CON_OPENFAIL: peer->ConnectRetryTimer = time(NULL) + INTERVAL_CONNECTRETRY; session_close_connection(peer); change_state(peer, STATE_ACTIVE, event); break; case EVNT_TIMER_CONNRETRY: peer->ConnectRetryTimer = time(NULL) + INTERVAL_CONNECTRETRY; session_connect(peer); break; default: change_state(peer, STATE_IDLE, event); break; } break; case STATE_ACTIVE: switch (event) { case EVNT_START: /* ignore */ break; case EVNT_CON_OPEN: session_tcp_established(peer); session_open(peer); peer->ConnectRetryTimer = 0; peer->holdtime = INTERVAL_HOLD_INITIAL; start_timer_holdtime(peer); change_state(peer, STATE_OPENSENT, event); break; case EVNT_CON_OPENFAIL: peer->ConnectRetryTimer = time(NULL) + INTERVAL_CONNECTRETRY; session_close_connection(peer); change_state(peer, STATE_ACTIVE, event); break; case EVNT_TIMER_CONNRETRY: peer->ConnectRetryTimer = time(NULL) + peer->holdtime; change_state(peer, STATE_CONNECT, event); session_connect(peer); break; default: change_state(peer, STATE_IDLE, event); break; } break; case STATE_OPENSENT: switch (event) { case EVNT_START: /* ignore */ break; case EVNT_STOP: session_notification(peer, ERR_CEASE, 0, NULL, 0); change_state(peer, STATE_IDLE, event); break; case EVNT_CON_CLOSED: session_close_connection(peer); peer->ConnectRetryTimer = time(NULL) + INTERVAL_CONNECTRETRY; change_state(peer, STATE_ACTIVE, event); break; case EVNT_CON_FATAL: change_state(peer, STATE_IDLE, event); break; case EVNT_TIMER_HOLDTIME: session_notification(peer, ERR_HOLDTIMEREXPIRED, 0, NULL, 0); change_state(peer, STATE_IDLE, event); break; case EVNT_RCVD_OPEN: /* parse_open calls change_state itself on failure */ if (parse_open(peer)) break; session_keepalive(peer); change_state(peer, STATE_OPENCONFIRM, event); break; case EVNT_RCVD_NOTIFICATION: if (parse_notification(peer)) { change_state(peer, STATE_IDLE, event); /* don't punish, capa negotiation */ peer->IdleHoldTimer = time(NULL); peer->IdleHoldTime /= 2; } else change_state(peer, STATE_IDLE, event); break; default: session_notification(peer, ERR_FSM, 0, NULL, 0); change_state(peer, STATE_IDLE, event); break; } break; case STATE_OPENCONFIRM: switch (event) { case EVNT_START: /* ignore */ break; case EVNT_STOP: session_notification(peer, ERR_CEASE, 0, NULL, 0); change_state(peer, STATE_IDLE, event); break; case EVNT_CON_CLOSED: case EVNT_CON_FATAL: change_state(peer, STATE_IDLE, event); break; case EVNT_TIMER_HOLDTIME: session_notification(peer, ERR_HOLDTIMEREXPIRED, 0, NULL, 0); change_state(peer, STATE_IDLE, event); break; case EVNT_TIMER_KEEPALIVE: session_keepalive(peer); break; case EVNT_RCVD_KEEPALIVE: start_timer_holdtime(peer); change_state(peer, STATE_ESTABLISHED, event); break; case EVNT_RCVD_NOTIFICATION: parse_notification(peer); change_state(peer, STATE_IDLE, event); break; default: session_notification(peer, ERR_FSM, 0, NULL, 0); change_state(peer, STATE_IDLE, event); break; } break; case STATE_ESTABLISHED: switch (event) { case EVNT_START: /* ignore */ break; case EVNT_STOP: session_notification(peer, ERR_CEASE, 0, NULL, 0); change_state(peer, STATE_IDLE, event); break; case EVNT_CON_CLOSED: case EVNT_CON_FATAL: change_state(peer, STATE_IDLE, event); break; case EVNT_TIMER_HOLDTIME: session_notification(peer, ERR_HOLDTIMEREXPIRED, 0, NULL, 0); change_state(peer, STATE_IDLE, event); break; case EVNT_TIMER_KEEPALIVE: session_keepalive(peer); break; case EVNT_RCVD_KEEPALIVE: start_timer_holdtime(peer); break; case EVNT_RCVD_UPDATE: start_timer_holdtime(peer); if (parse_update(peer)) change_state(peer, STATE_IDLE, event); else start_timer_holdtime(peer); break; case EVNT_RCVD_NOTIFICATION: parse_notification(peer); change_state(peer, STATE_IDLE, event); break; default: session_notification(peer, ERR_FSM, 0, NULL, 0); change_state(peer, STATE_IDLE, event); break; } break; } } int timer_due(time_t timer) { if (timer > 0 && timer <= time(NULL)) return (1); return (0); } void start_timer_holdtime(struct peer *peer) { if (peer->holdtime > 0) peer->HoldTimer = time(NULL) + peer->holdtime; else peer->HoldTimer = 0; } void start_timer_keepalive(struct peer *peer) { if (peer->holdtime > 0) peer->KeepaliveTimer = time(NULL) + peer->holdtime / 3; else peer->KeepaliveTimer = 0; } void session_close_connection(struct peer *peer) { if (peer->fd != -1) { shutdown(peer->fd, SHUT_RDWR); close(peer->fd); } peer->fd = peer->wbuf.fd = -1; } void change_state(struct peer *peer, enum session_state state, enum session_events event) { struct mrt_config *mrt; switch (state) { case STATE_IDLE: /* * try to write out what's buffered (maybe a notification), * don't bother if it fails */ if (peer->state >= STATE_OPENSENT && peer->wbuf.queued) msgbuf_write(&peer->wbuf); /* * we must start the timer for the next EVNT_START * if we are coming here due to an error and the * session was not established successfully before, the * starttimerinterval needs to be exponentially increased */ if (peer->IdleHoldTime == 0) peer->IdleHoldTime = INTERVAL_IDLE_HOLD_INITIAL; peer->holdtime = INTERVAL_HOLD_INITIAL; peer->ConnectRetryTimer = 0; peer->KeepaliveTimer = 0; peer->HoldTimer = 0; peer->IdleHoldResetTimer = 0; session_close_connection(peer); msgbuf_clear(&peer->wbuf); free(peer->rbuf); peer->rbuf = NULL; if (peer->state == STATE_ESTABLISHED) session_down(peer); if (event != EVNT_STOP && !peer->conf.cloned) { peer->IdleHoldTimer = time(NULL) + peer->IdleHoldTime; if (event != EVNT_NONE && peer->IdleHoldTime < MAX_IDLE_HOLD/2) peer->IdleHoldTime *= 2; } if (peer->state != STATE_NONE && peer->conf.cloned) peer->conf.reconf_action = RECONF_DELETE; break; case STATE_CONNECT: break; case STATE_ACTIVE: break; case STATE_OPENSENT: break; case STATE_OPENCONFIRM: break; case STATE_ESTABLISHED: if (peer->IdleHoldTime > INTERVAL_IDLE_HOLD_INITIAL) peer->IdleHoldResetTimer = time(NULL) + peer->IdleHoldTime; session_up(peer); break; default: /* something seriously fucked */ break; } log_statechange(peer, state, event); LIST_FOREACH(mrt, &mrt_l, list) { if (mrt->type != MRT_ALL_IN && mrt->type != MRT_ALL_OUT) continue; if ((mrt->peer_id == 0 && mrt->group_id == 0) || mrt->peer_id == peer->conf.id || mrt->group_id == peer->conf.groupid) mrt_dump_state(mrt, peer->state, state, &peer->conf, conf); } peer->state = state; } void session_accept(int listenfd) { int connfd; int opt; socklen_t len; struct sockaddr_storage cliaddr; struct peer *p = NULL; len = sizeof(cliaddr); if ((connfd = accept(listenfd, (struct sockaddr *)&cliaddr, &len)) == -1) { if (errno == EWOULDBLOCK || errno == EINTR) return; else log_warn("accept"); } p = getpeerbyip((struct sockaddr *)&cliaddr); if (p != NULL && (p->state == STATE_CONNECT || p->state == STATE_ACTIVE)) { if (p->fd != -1) { if (p->state == STATE_CONNECT) session_close_connection(p); else { shutdown(connfd, SHUT_RDWR); close(connfd); return; } } if (p->conf.auth.method != AUTH_NONE && sysdep.no_pfkey) { log_peer_warnx(&p->conf, "ipsec or md5sig configured but not available"); shutdown(connfd, SHUT_RDWR); close(connfd); return; } if (p->conf.auth.method == AUTH_MD5SIG) { if (sysdep.no_md5sig) { log_peer_warnx(&p->conf, "md5sig configured but not available"); shutdown(connfd, SHUT_RDWR); close(connfd); return; } len = sizeof(opt); if (getsockopt(connfd, IPPROTO_TCP, TCP_MD5SIG, &opt, &len) == -1) fatal("getsockopt TCP_MD5SIG"); if (!opt) { /* non-md5'd connection! */ log_peer_warnx(&p->conf, "connection attempt without md5 signature"); shutdown(connfd, SHUT_RDWR); close(connfd); return; } } p->fd = p->wbuf.fd = connfd; if (session_setup_socket(p)) { shutdown(connfd, SHUT_RDWR); close(connfd); return; } session_socket_blockmode(connfd, BM_NONBLOCK); bgp_fsm(p, EVNT_CON_OPEN); } else { log_conn_attempt(p, (struct sockaddr *)&cliaddr); shutdown(connfd, SHUT_RDWR); close(connfd); } } int session_connect(struct peer *peer) { int opt = 1; struct sockaddr *sa; /* * we do not need the overcomplicated collision detection rfc1771 * describes; we simply make sure there is only ever one concurrent * tcp connection per peer. */ if (peer->fd != -1) return (-1); if ((peer->fd = socket(peer->conf.remote_addr.af, SOCK_STREAM, IPPROTO_TCP)) == -1) { log_peer_warn(&peer->conf, "session_connect socket"); bgp_fsm(peer, EVNT_CON_OPENFAIL); return (-1); } if (peer->conf.auth.method != AUTH_NONE && sysdep.no_pfkey) { log_peer_warnx(&peer->conf, "ipsec or md5sig configured but not available"); bgp_fsm(peer, EVNT_CON_OPENFAIL); return (-1); } if (peer->conf.auth.method == AUTH_MD5SIG) { if (sysdep.no_md5sig) { log_peer_warnx(&peer->conf, "md5sig configured but not available"); bgp_fsm(peer, EVNT_CON_OPENFAIL); return (-1); } if (setsockopt(peer->fd, IPPROTO_TCP, TCP_MD5SIG, &opt, sizeof(opt)) == -1) { log_peer_warn(&peer->conf, "setsockopt md5sig"); bgp_fsm(peer, EVNT_CON_OPENFAIL); return (-1); } } peer->wbuf.fd = peer->fd; /* if update source is set we need to bind() */ if (peer->conf.local_addr.af) { sa = addr2sa(&peer->conf.local_addr, 0); if (bind(peer->fd, sa, sa->sa_len) == -1) { log_peer_warn(&peer->conf, "session_connect bind"); bgp_fsm(peer, EVNT_CON_OPENFAIL); return (-1); } } if (session_setup_socket(peer)) { bgp_fsm(peer, EVNT_CON_OPENFAIL); return (-1); } session_socket_blockmode(peer->fd, BM_NONBLOCK); sa = addr2sa(&peer->conf.remote_addr, BGP_PORT); if (connect(peer->fd, sa, sa->sa_len) == -1) { if (errno != EINPROGRESS) { log_peer_warn(&peer->conf, "connect"); bgp_fsm(peer, EVNT_CON_OPENFAIL); return (-1); } } else bgp_fsm(peer, EVNT_CON_OPEN); return (0); } int session_setup_socket(struct peer *p) { int ttl = p->conf.distance; int pre = IPTOS_PREC_INTERNETCONTROL; int nodelay = 1; int bsize; if (p->conf.ebgp && p->sa_remote.ss_family == AF_INET) /* set TTL to foreign router's distance - 1=direct n=multihop */ if (setsockopt(p->fd, IPPROTO_IP, IP_TTL, &ttl, sizeof(ttl)) == -1) { log_peer_warn(&p->conf, "session_setup_socket setsockopt TTL"); return (-1); } if (p->conf.ebgp && p->sa_remote.ss_family == AF_INET6) /* set hoplimit to foreign router's distance */ if (setsockopt(p->fd, IPPROTO_IPV6, IPV6_HOPLIMIT, &ttl, sizeof(ttl)) == -1) { log_peer_warn(&p->conf, "session_setup_socket setsockopt hoplimit"); return (-1); } /* set TCP_NODELAY */ if (setsockopt(p->fd, IPPROTO_TCP, TCP_NODELAY, &nodelay, sizeof(nodelay)) == -1) { log_peer_warn(&p->conf, "session_setup_socket setsockopt TCP_NODELAY"); return (-1); } /* set precedence, see rfc1771 appendix 5 */ if (p->sa_remote.ss_family == AF_INET && setsockopt(p->fd, IPPROTO_IP, IP_TOS, &pre, sizeof(pre)) == -1) { log_peer_warn(&p->conf, "session_setup_socket setsockopt TOS"); return (-1); } /* only increase bufsize (and thus window) if md5 or ipsec is in use */ if (p->conf.auth.method != AUTH_NONE) { /* try to increase bufsize. no biggie if it fails */ bsize = 65535; while (setsockopt(p->fd, SOL_SOCKET, SO_RCVBUF, &bsize, sizeof(bsize)) == -1) bsize /= 2; bsize = 65535; while (setsockopt(p->fd, SOL_SOCKET, SO_SNDBUF, &bsize, sizeof(bsize)) == -1) bsize /= 2; } return (0); } void session_socket_blockmode(int fd, enum blockmodes bm) { int flags; if ((flags = fcntl(fd, F_GETFL, 0)) == -1) fatal("fnctl F_GETFL"); if (bm == BM_NONBLOCK) flags |= O_NONBLOCK; else flags &= ~O_NONBLOCK; if ((flags = fcntl(fd, F_SETFL, flags)) == -1) fatal("fnctl F_SETFL"); } void session_tcp_established(struct peer *peer) { socklen_t len; len = sizeof(peer->sa_local); if (getsockname(peer->fd, (struct sockaddr *)&peer->sa_local, &len) == -1) log_warn("getsockname"); len = sizeof(peer->sa_remote); if (getpeername(peer->fd, (struct sockaddr *)&peer->sa_remote, &len) == -1) log_warn("getpeername"); } void session_open(struct peer *p) { struct msg_open msg; struct buf *buf; struct mrt_config *mrt; u_int16_t len; int errs = 0; u_int8_t op_type, op_len = 0, optparamlen = 0; u_int8_t capa_code, capa_len; struct capa_mp capa_mp_v4; if (p->capa.announce) { if (p->capa.ann_mp) { /* multiprotocol extensions, RFC 2858 */ bzero(&capa_mp_v4, sizeof(capa_mp_v4)); capa_mp_v4.afi = htons(AFI_IPv4); capa_mp_v4.safi = SAFI_UNICAST; op_len += 6; /* 1 code + 1 len + 4 data */ } if (p->capa.ann_refresh) { /* route refresh, RFC 2918 */ op_len += 2; /* 1 code + 1 len, no data */ } if (op_len > 0) optparamlen = sizeof(op_type) + sizeof(op_len) + op_len; } len = MSGSIZE_OPEN_MIN + optparamlen; memset(&msg.header.marker, 0xff, sizeof(msg.header.marker)); msg.header.len = htons(len); msg.header.type = OPEN; msg.version = 4; msg.myas = htons(conf->as); if (p->conf.holdtime) msg.holdtime = htons(p->conf.holdtime); else msg.holdtime = htons(conf->holdtime); msg.bgpid = conf->bgpid; /* is already in network byte order */ msg.optparamlen = optparamlen; if ((buf = buf_open(len)) == NULL) { bgp_fsm(p, EVNT_CON_FATAL); return; } errs += buf_add(buf, &msg.header.marker, sizeof(msg.header.marker)); errs += buf_add(buf, &msg.header.len, sizeof(msg.header.len)); errs += buf_add(buf, &msg.header.type, sizeof(msg.header.type)); errs += buf_add(buf, &msg.version, sizeof(msg.version)); errs += buf_add(buf, &msg.myas, sizeof(msg.myas)); errs += buf_add(buf, &msg.holdtime, sizeof(msg.holdtime)); errs += buf_add(buf, &msg.bgpid, sizeof(msg.bgpid)); errs += buf_add(buf, &msg.optparamlen, sizeof(msg.optparamlen)); if (p->capa.announce && optparamlen) { op_type = OPT_PARAM_CAPABILITIES; errs += buf_add(buf, &op_type, sizeof(op_type)); errs += buf_add(buf, &op_len, sizeof(op_len)); if (p->capa.ann_mp) { /* multiprotocol extensions, RFC 2858 */ capa_code = CAPA_MP; capa_len = 4; errs += buf_add(buf, &capa_code, sizeof(capa_code)); errs += buf_add(buf, &capa_len, sizeof(capa_len)); errs += buf_add(buf, &capa_mp_v4.afi, sizeof(capa_mp_v4.afi)); errs += buf_add(buf, &capa_mp_v4.pad, sizeof(capa_mp_v4.pad)); errs += buf_add(buf, &capa_mp_v4.safi, sizeof(capa_mp_v4.safi)); } if (p->capa.ann_refresh) { /* route refresh, RFC 2918 */ capa_code = CAPA_REFRESH; capa_len = 0; errs += buf_add(buf, &capa_code, sizeof(capa_code)); errs += buf_add(buf, &capa_len, sizeof(capa_len)); } } if (errs == 0) { LIST_FOREACH(mrt, &mrt_l, list) { if (mrt->type != MRT_ALL_OUT) continue; if ((mrt->peer_id == 0 && mrt->group_id == 0) || mrt->peer_id == p->conf.id || mrt->group_id == p->conf.groupid) mrt_dump_bgp_msg(mrt, buf->buf, len, &p->conf, conf); } if (buf_close(&p->wbuf, buf) == -1) { log_peer_warn(&p->conf, "session_open buf_close"); buf_free(buf); bgp_fsm(p, EVNT_CON_FATAL); return; } } else { buf_free(buf); bgp_fsm(p, EVNT_CON_FATAL); return; } p->stats.msg_sent_open++; } void session_keepalive(struct peer *peer) { struct msg_header msg; struct buf *buf; struct mrt_config *mrt; ssize_t len; int errs = 0; len = MSGSIZE_KEEPALIVE; memset(&msg.marker, 0xff, sizeof(msg.marker)); msg.len = htons(len); msg.type = KEEPALIVE; if ((buf = buf_open(len)) == NULL) { bgp_fsm(peer, EVNT_CON_FATAL); return; } errs += buf_add(buf, &msg.marker, sizeof(msg.marker)); errs += buf_add(buf, &msg.len, sizeof(msg.len)); errs += buf_add(buf, &msg.type, sizeof(msg.type)); if (errs > 0) { buf_free(buf); bgp_fsm(peer, EVNT_CON_FATAL); return; } LIST_FOREACH(mrt, &mrt_l, list) { if (mrt->type != MRT_ALL_OUT) continue; if ((mrt->peer_id == 0 && mrt->group_id == 0) || mrt->peer_id == peer->conf.id || mrt->group_id == peer->conf.groupid) mrt_dump_bgp_msg(mrt, buf->buf, len, &peer->conf, conf); } if (buf_close(&peer->wbuf, buf) == -1) { log_peer_warn(&peer->conf, "session_keepalive buf_close"); buf_free(buf); bgp_fsm(peer, EVNT_CON_FATAL); return; } start_timer_keepalive(peer); peer->stats.msg_sent_keepalive++; } void session_update(u_int32_t peerid, void *data, size_t datalen) { struct peer *p; struct msg_header msg; struct buf *buf; struct mrt_config *mrt; ssize_t len; int errs = 0; if ((p = getpeerbyid(peerid)) == NULL) { log_warnx("no such peer: id=%u", peerid); return; } if (p->state != STATE_ESTABLISHED) return; len = MSGSIZE_HEADER + datalen; memset(&msg.marker, 0xff, sizeof(msg.marker)); msg.len = htons(len); msg.type = UPDATE; if ((buf = buf_open(len)) == NULL) { bgp_fsm(p, EVNT_CON_FATAL); return; } errs += buf_add(buf, &msg.marker, sizeof(msg.marker)); errs += buf_add(buf, &msg.len, sizeof(msg.len)); errs += buf_add(buf, &msg.type, sizeof(msg.type)); errs += buf_add(buf, data, datalen); if (errs > 0) { buf_free(buf); bgp_fsm(p, EVNT_CON_FATAL); return; } LIST_FOREACH(mrt, &mrt_l, list) { if (mrt->type != MRT_ALL_OUT && mrt->type != MRT_UPDATE_OUT) continue; if ((mrt->peer_id == 0 && mrt->group_id == 0) || mrt->peer_id == p->conf.id || mrt->group_id == p->conf.groupid) mrt_dump_bgp_msg(mrt, buf->buf, len, &p->conf, conf); } if (buf_close(&p->wbuf, buf) == -1) { log_peer_warn(&p->conf, "session_update: buf_close"); buf_free(buf); bgp_fsm(p, EVNT_CON_FATAL); return; } start_timer_keepalive(p); p->stats.msg_sent_update++; } void session_notification(struct peer *peer, u_int8_t errcode, u_int8_t subcode, void *data, ssize_t datalen) { struct msg_header msg; struct buf *buf; struct mrt_config *mrt; ssize_t len; int errs = 0; len = MSGSIZE_NOTIFICATION_MIN + datalen; memset(&msg.marker, 0xff, sizeof(msg.marker)); msg.len = htons(len); msg.type = NOTIFICATION; if ((buf = buf_open(len)) == NULL) { bgp_fsm(peer, EVNT_CON_FATAL); return; } errs += buf_add(buf, &msg.marker, sizeof(msg.marker)); errs += buf_add(buf, &msg.len, sizeof(msg.len)); errs += buf_add(buf, &msg.type, sizeof(msg.type)); errs += buf_add(buf, &errcode, sizeof(errcode)); errs += buf_add(buf, &subcode, sizeof(subcode)); if (datalen > 0) errs += buf_add(buf, data, datalen); if (errs > 0) { buf_free(buf); bgp_fsm(peer, EVNT_CON_FATAL); return; } LIST_FOREACH(mrt, &mrt_l, list) { if (mrt->type != MRT_ALL_OUT) continue; if ((mrt->peer_id == 0 && mrt->group_id == 0) || mrt->peer_id == peer->conf.id || mrt->group_id == peer->conf.groupid) mrt_dump_bgp_msg(mrt, buf->buf, len, &peer->conf, conf); } if (buf_close(&peer->wbuf, buf) == -1) { log_peer_warn(&peer->conf, "session_notification: buf_close"); buf_free(buf); bgp_fsm(peer, EVNT_CON_FATAL); return; } peer->stats.msg_sent_notification++; } int session_dispatch_msg(struct pollfd *pfd, struct peer *p) { ssize_t n, rpos, av, left; socklen_t len; int error; u_int16_t msglen; u_int8_t msgtype; if (p->state == STATE_CONNECT) { if (pfd->revents & POLLOUT) { if (pfd->revents & POLLIN) { /* error occurred */ len = sizeof(error); if (getsockopt(pfd->fd, SOL_SOCKET, SO_ERROR, &error, &len) == -1 || error) { if (error) errno = error; log_peer_warn(&p->conf, "socket error"); bgp_fsm(p, EVNT_CON_OPENFAIL); return (1); } } bgp_fsm(p, EVNT_CON_OPEN); return (1); } if (pfd->revents & POLLHUP) { bgp_fsm(p, EVNT_CON_OPENFAIL); return (1); } if (pfd->revents & (POLLERR|POLLNVAL)) { bgp_fsm(p, EVNT_CON_FATAL); return (1); } return (0); } if (pfd->revents & POLLHUP) { bgp_fsm(p, EVNT_CON_CLOSED); return (1); } if (pfd->revents & (POLLERR|POLLNVAL)) { bgp_fsm(p, EVNT_CON_FATAL); return (1); } if (pfd->revents & POLLOUT && p->wbuf.queued) { if ((error = msgbuf_write(&p->wbuf)) < 0) { if (error == -2) log_peer_warnx(&p->conf, "Connection closed"); else log_peer_warn(&p->conf, "write error"); bgp_fsm(p, EVNT_CON_FATAL); return (1); } if (!(pfd->revents & POLLIN)) return (1); } if (pfd->revents & POLLIN) { if ((n = read(p->fd, p->rbuf->buf + p->rbuf->wpos, sizeof(p->rbuf->buf) - p->rbuf->wpos)) == -1) { if (errno != EINTR && errno != EAGAIN) { log_peer_warn(&p->conf, "read error"); bgp_fsm(p, EVNT_CON_FATAL); } return (1); } if (n == 0) { /* connection closed */ bgp_fsm(p, EVNT_CON_CLOSED); return (1); } rpos = 0; av = p->rbuf->wpos + n; p->stats.last_read = time(NULL); /* * session might drop to IDLE -> buffers deallocated * we MUST check rbuf != NULL before use */ for (;;) { if (rpos + MSGSIZE_HEADER > av) break; if (p->rbuf == NULL) break; if (parse_header(p, p->rbuf->buf + rpos, &msglen, &msgtype) == -1) return (0); if (rpos + msglen > av) break; p->rbuf->rptr = p->rbuf->buf + rpos; switch (msgtype) { case OPEN: bgp_fsm(p, EVNT_RCVD_OPEN); p->stats.msg_rcvd_open++; break; case UPDATE: bgp_fsm(p, EVNT_RCVD_UPDATE); p->stats.msg_rcvd_update++; break; case NOTIFICATION: bgp_fsm(p, EVNT_RCVD_NOTIFICATION); p->stats.msg_rcvd_notification++; break; case KEEPALIVE: bgp_fsm(p, EVNT_RCVD_KEEPALIVE); p->stats.msg_rcvd_keepalive++; break; case RREFRESH: parse_refresh(p); p->stats.msg_rcvd_rrefresh++; break; default: /* cannot happen */ session_notification(p, ERR_HEADER, ERR_HDR_TYPE, &msgtype, 1); log_warnx("received message with " "unknown type %u", msgtype); } rpos += msglen; } if (p->rbuf == NULL) return (1); if (rpos < av) { left = av - rpos; memcpy(&p->rbuf->buf, p->rbuf->buf + rpos, left); p->rbuf->wpos = left; } else p->rbuf->wpos = 0; return (1); } return (0); } int parse_header(struct peer *peer, u_char *data, u_int16_t *len, u_int8_t *type) { struct mrt_config *mrt; u_char *p; u_char one = 0xff; int i; u_int16_t olen; /* caller MUST make sure we are getting 19 bytes! */ p = data; for (i = 0; i < 16; i++) { if (memcmp(p, &one, 1)) { log_peer_warnx(&peer->conf, "sync error"); session_notification(peer, ERR_HEADER, ERR_HDR_SYNC, NULL, 0); bgp_fsm(peer, EVNT_CON_FATAL); return (-1); } p++; } memcpy(&olen, p, 2); *len = ntohs(olen); p += 2; memcpy(type, p, 1); if (*len < MSGSIZE_HEADER || *len > MAX_PKTSIZE) { log_peer_warnx(&peer->conf, "received message: illegal length: %u byte", *len); session_notification(peer, ERR_HEADER, ERR_HDR_LEN, &olen, sizeof(olen)); return (-1); } switch (*type) { case OPEN: if (*len < MSGSIZE_OPEN_MIN) { log_peer_warnx(&peer->conf, "received OPEN: illegal len: %u byte", *len); session_notification(peer, ERR_HEADER, ERR_HDR_LEN, &olen, sizeof(olen)); return (-1); } break; case NOTIFICATION: if (*len < MSGSIZE_NOTIFICATION_MIN) { log_peer_warnx(&peer->conf, "received NOTIFICATION: illegal len: %u byte", *len); session_notification(peer, ERR_HEADER, ERR_HDR_LEN, &olen, sizeof(olen)); return (-1); } break; case UPDATE: if (*len < MSGSIZE_UPDATE_MIN) { log_peer_warnx(&peer->conf, "received UPDATE: illegal len: %u byte", *len); session_notification(peer, ERR_HEADER, ERR_HDR_LEN, &olen, sizeof(olen)); return (-1); } break; case KEEPALIVE: if (*len != MSGSIZE_KEEPALIVE) { log_peer_warnx(&peer->conf, "received KEEPALIVE: illegal len: %u byte", *len); session_notification(peer, ERR_HEADER, ERR_HDR_LEN, &olen, sizeof(olen)); return (-1); } break; case RREFRESH: if (*len != MSGSIZE_RREFRESH) { log_peer_warnx(&peer->conf, "received RREFRESH: illegal len: %u byte", *len); session_notification(peer, ERR_HEADER, ERR_HDR_LEN, &olen, sizeof(olen)); return (-1); } break; default: log_peer_warnx(&peer->conf, "received msg with unknown type %u", *type); session_notification(peer, ERR_HEADER, ERR_HDR_TYPE, type, 1); return (-1); } LIST_FOREACH(mrt, &mrt_l, list) { if (mrt->type != MRT_ALL_IN && (mrt->type != MRT_UPDATE_IN || *type != UPDATE)) continue; if ((mrt->peer_id == 0 && mrt->group_id == 0) || mrt->peer_id == peer->conf.id || mrt->group_id == peer->conf.groupid) mrt_dump_bgp_msg(mrt, data, *len, &peer->conf, conf); } return (0); } int parse_open(struct peer *peer) { u_char *p, *op_val; u_int8_t version, rversion; u_int16_t as, msglen; u_int16_t holdtime, oholdtime, myholdtime; u_int32_t bgpid; u_int8_t optparamlen, plen; u_int8_t op_type, op_len; p = peer->rbuf->rptr; p += MSGSIZE_HEADER_MARKER; memcpy(&msglen, p, sizeof(msglen)); msglen = ntohs(msglen); p = peer->rbuf->rptr; p += MSGSIZE_HEADER; /* header is already checked */ memcpy(&version, p, sizeof(version)); p += sizeof(version); if (version != BGP_VERSION) { log_peer_warnx(&peer->conf, "peer wants unrecognized version %u", version); if (version > BGP_VERSION) rversion = version - BGP_VERSION; else rversion = BGP_VERSION; session_notification(peer, ERR_OPEN, ERR_OPEN_VERSION, &rversion, sizeof(rversion)); change_state(peer, STATE_IDLE, EVNT_RCVD_OPEN); return (-1); } memcpy(&as, p, sizeof(as)); p += sizeof(as); /* if remote-as is zero and it's a cloned neighbor, accept any */ if (peer->conf.cloned && !peer->conf.remote_as) peer->conf.remote_as = ntohs(as); if (peer->conf.remote_as != ntohs(as)) { log_peer_warnx(&peer->conf, "peer sent wrong AS %u", ntohs(as)); session_notification(peer, ERR_OPEN, ERR_OPEN_AS, NULL, 0); change_state(peer, STATE_IDLE, EVNT_RCVD_OPEN); return (-1); } memcpy(&oholdtime, p, sizeof(oholdtime)); p += sizeof(oholdtime); holdtime = ntohs(oholdtime); if (holdtime && holdtime < peer->conf.min_holdtime) { log_peer_warnx(&peer->conf, "peer requests unacceptable holdtime %u", holdtime); session_notification(peer, ERR_OPEN, ERR_OPEN_HOLDTIME, NULL, 0); change_state(peer, STATE_IDLE, EVNT_RCVD_OPEN); return (-1); } myholdtime = peer->conf.holdtime; if (!myholdtime) myholdtime = conf->holdtime; if (holdtime < myholdtime) peer->holdtime = holdtime; else peer->holdtime = myholdtime; memcpy(&bgpid, p, sizeof(bgpid)); p += sizeof(bgpid); /* check bgpid for validity, must be a valid ip address - HOW? */ /* if ( bgpid invalid ) { log_peer_warnx(&peer->conf, "peer BGPID %lu unacceptable", ntohl(bgpid)); session_notification(peer, ERR_OPEN, ERR_OPEN_BGPID, NULL, 0); change_state(peer, STATE_IDLE, EVNT_RCVD_OPEN); return (-1); } */ peer->remote_bgpid = bgpid; memcpy(&optparamlen, p, sizeof(optparamlen)); p += sizeof(optparamlen); if (optparamlen > msglen - MSGSIZE_OPEN_MIN) { log_peer_warnx(&peer->conf, "corrupt OPEN message received: length mismatch"); session_notification(peer, ERR_OPEN, 0, NULL, 0); change_state(peer, STATE_IDLE, EVNT_RCVD_OPEN); return (-1); } plen = optparamlen; while (plen > 0) { if (plen < 2) { log_peer_warnx(&peer->conf, "corrupt OPEN message received, len wrong"); session_notification(peer, ERR_OPEN, 0, NULL, 0); change_state(peer, STATE_IDLE, EVNT_RCVD_OPEN); return (-1); } memcpy(&op_type, p, sizeof(op_type)); p += sizeof(op_type); plen -= sizeof(op_type); memcpy(&op_len, p, sizeof(op_len)); p += sizeof(op_len); plen -= sizeof(op_len); if (op_len > 0) { if (plen < op_len) { log_peer_warnx(&peer->conf, "corrupt OPEN message received, len wrong"); session_notification(peer, ERR_OPEN, 0, NULL, 0); change_state(peer, STATE_IDLE, EVNT_RCVD_OPEN); return (-1); } op_val = p; p += op_len; plen -= op_len; } else op_val = NULL; switch (op_type) { case OPT_PARAM_CAPABILITIES: /* RFC 3392 */ if (parse_capabilities(peer, op_val, op_len) == -1) { session_notification(peer, ERR_OPEN, 0, NULL, 0); change_state(peer, STATE_IDLE, EVNT_RCVD_OPEN); return (-1); } break; case OPT_PARAM_AUTH: /* deprecated */ default: /* * unsupported type * the RFCs tell us to leave the data section empty * and notify the peer with ERR_OPEN, ERR_OPEN_OPT. * How the peer should know _which_ optional parameter * we don't support is beyond me. */ log_peer_warnx(&peer->conf, "received OPEN message with unsupported optional " "parameter: type %u", op_type); session_notification(peer, ERR_OPEN, ERR_OPEN_OPT, NULL, 0); change_state(peer, STATE_IDLE, EVNT_RCVD_OPEN); peer->IdleHoldTimer = time(NULL); /* no punish */ peer->IdleHoldTime /= 2; return (-1); /* not reached */ } } return (0); } int parse_update(struct peer *peer) { u_char *p; u_int16_t datalen; /* * we pass the message verbatim to the rde. * in case of errors the whole session is reset with a * notification anyway, we only need to know the peer */ p = peer->rbuf->rptr; p += MSGSIZE_HEADER_MARKER; memcpy(&datalen, p, sizeof(datalen)); datalen = ntohs(datalen); p = peer->rbuf->rptr; p += MSGSIZE_HEADER; /* header is already checked */ datalen -= MSGSIZE_HEADER; if (imsg_compose(&ibuf_rde, IMSG_UPDATE, peer->conf.id, p, datalen) == -1) return (-1); return (0); } int parse_refresh(struct peer *peer) { u_char *p; struct rrefresh r; p = peer->rbuf->rptr; p += MSGSIZE_HEADER; /* header is already checked */ /* afi, 2 byte */ memcpy(&r.afi, p, sizeof(r.afi)); r.afi = ntohs(r.afi); p += 2; /* reserved, 1 byte */ p += 1; /* safi, 1 byte */ memcpy(&r.safi, p, sizeof(r.safi)); /* afi/safi unchecked - unrecognized values will be ignored anyway */ if (imsg_compose(&ibuf_rde, IMSG_REFRESH, peer->conf.id, &r, sizeof(r)) == -1) return (-1); return (0); } int parse_notification(struct peer *peer) { u_char *p; u_int8_t errcode; u_int8_t subcode; u_int16_t datalen; u_int8_t capa_code; u_int8_t capa_len; /* just log */ p = peer->rbuf->rptr; p += MSGSIZE_HEADER_MARKER; memcpy(&datalen, p, sizeof(datalen)); datalen = ntohs(datalen); p = peer->rbuf->rptr; p += MSGSIZE_HEADER; /* header is already checked */ datalen -= MSGSIZE_HEADER; memcpy(&errcode, p, sizeof(errcode)); p += sizeof(errcode); datalen -= sizeof(errcode); memcpy(&subcode, p, sizeof(subcode)); p += sizeof(subcode); datalen -= sizeof(subcode); log_notification(peer, errcode, subcode, p, datalen); if (errcode == ERR_OPEN && subcode == ERR_OPEN_CAPA) { if (datalen == 0) { /* zebra likes to send those.. humbug */ log_peer_warnx(&peer->conf, "received \"unsupported " "capability\" notification without data part, " "disabling capability announcements alltogether"); peer->capa.announce = 0; } while (datalen > 0) { if (datalen < 2) { log_peer_warnx(&peer->conf, "parse_notification: " "expect len >= 2, len is %u", datalen); return (-1); } memcpy(&capa_code, p, sizeof(capa_code)); p += sizeof(capa_code); datalen -= sizeof(capa_code); memcpy(&capa_len, p, sizeof(capa_len)); p += sizeof(capa_len); datalen -= sizeof(capa_len); if (datalen < capa_len) { log_peer_warnx(&peer->conf, "parse_notification: capa_len %u exceeds" "remaining msg length", capa_len); return (-1); } p += capa_len; datalen -= capa_len; switch (capa_code) { case CAPA_MP: peer->capa.ann_mp = 0; log_peer_warnx(&peer->conf, "disabling multiprotocol capability"); break; case CAPA_REFRESH: peer->capa.ann_refresh = 0; log_peer_warnx(&peer->conf, "disabling route refresh capability"); break; default: /* should not happen... */ log_peer_warnx(&peer->conf, "received " "\"unsupported capability\" notification " "for unknown capability %u, disabling " "capability announcements alltogether", capa_code); peer->capa.announce = 0; break; } } return (1); } if (errcode == ERR_OPEN && subcode == ERR_OPEN_OPT) { peer->capa.announce = 0; return (1); } return (0); } int parse_capabilities(struct peer *peer, u_char *d, u_int16_t dlen) { u_int16_t len; u_int8_t capa_code; u_int8_t capa_len; u_char *capa_val; u_int16_t mp_afi; u_int8_t mp_safi; len = dlen; while (len > 0) { if (len < 2) { log_peer_warnx(&peer->conf, "parse_capabilities: " "expect len >= 2, len is %u", len); return (-1); } memcpy(&capa_code, d, sizeof(capa_code)); d += sizeof(capa_code); len -= sizeof(capa_code); memcpy(&capa_len, d, sizeof(capa_len)); d += sizeof(capa_len); len -= sizeof(capa_len); if (capa_len > 0) { if (len < capa_len) { log_peer_warnx(&peer->conf, "parse_capabilities: " "len %u smaller than capa_len %u", len, capa_len); return (-1); } capa_val = d; d += capa_len; len -= capa_len; } else capa_val = NULL; switch (capa_code) { case CAPA_MP: /* RFC 2858 */ if (capa_len != 4) { log_peer_warnx(&peer->conf, "parse_capabilities: " "expect len 4, len is %u", capa_len); return (-1); } memcpy(&mp_afi, capa_val, sizeof(mp_afi)); mp_afi = ntohs(mp_afi); memcpy(&mp_safi, capa_val + 3, sizeof(mp_safi)); switch (mp_afi) { case AFI_IPv4: if (mp_safi < 1 || mp_safi > 3) { log_peer_warnx(&peer->conf, "parse_capabilities: AFI IPv4, " "mp_safi %u illegal", mp_safi); return (-1); } peer->capa.mp_v4 = mp_safi; break; case AFI_IPv6: if (mp_safi < 1 || mp_safi > 3) { log_peer_warnx(&peer->conf, "parse_capabilities: AFI IPv6, " "mp_safi %u illegal", mp_safi); return (-1); } peer->capa.mp_v6 = mp_safi; break; default: /* ignore */ break; } break; case CAPA_REFRESH: peer->capa.refresh = 1; break; default: break; } } return (0); } void session_dispatch_imsg(struct imsgbuf *ibuf, int idx, u_int *listener_cnt) { struct imsg imsg; struct mrt_config xmrt; struct mrt_config *mrt; struct peer_config *pconf; struct peer *p, *next; struct listen_addr *la, *nla; u_char *data; enum reconf_action reconf; int n; u_int8_t errcode, subcode; if ((n = imsg_read(ibuf)) == -1) fatal("session_dispatch_imsg: imsg_read error"); if (n == 0) /* connection closed */ fatal("session_dispatch_imsg: pipe closed"); for (;;) { if ((n = imsg_get(ibuf, &imsg)) == -1) fatal("session_dispatch_imsg: imsg_get error"); if (n == 0) break; switch (imsg.hdr.type) { case IMSG_RECONF_CONF: if (idx != PFD_PIPE_MAIN) fatalx("reconf request not from parent"); if ((nconf = malloc(sizeof(struct bgpd_config))) == NULL) fatal(NULL); memcpy(nconf, imsg.data, sizeof(struct bgpd_config)); if ((nconf->listen_addrs = calloc(1, sizeof(struct listen_addrs))) == NULL) fatal(NULL); TAILQ_INIT(nconf->listen_addrs); npeers = NULL; init_conf(nconf); pending_reconf = 1; break; case IMSG_RECONF_PEER: if (idx != PFD_PIPE_MAIN) fatalx("reconf request not from parent"); pconf = imsg.data; p = getpeerbyaddr(&pconf->remote_addr); if (p == NULL) { if ((p = calloc(1, sizeof(struct peer))) == NULL) fatal("new_peer"); p->state = STATE_NONE; p->next = npeers; npeers = p; reconf = RECONF_REINIT; } else reconf = RECONF_KEEP; memcpy(&p->conf, pconf, sizeof(struct peer_config)); p->conf.reconf_action = reconf; break; case IMSG_RECONF_LISTENER: if (idx != PFD_PIPE_MAIN) fatalx("reconf request not from parent"); nla = imsg.data; TAILQ_FOREACH(la, conf->listen_addrs, entry) { if (!la_cmp(la, nla)) break; } if (la == NULL) { la = calloc(1, sizeof(struct listen_addr)); if (la == NULL) fatal(NULL); memcpy(&la->sa, &nla->sa, sizeof(la->sa)); la->fd = nla->fd; la->flags = nla->flags; la->reconf = RECONF_REINIT; TAILQ_INSERT_TAIL(nconf->listen_addrs, la, entry); } else { la->reconf = RECONF_KEEP; } break; case IMSG_RECONF_DONE: if (idx != PFD_PIPE_MAIN) fatalx("reconf request not from parent"); if (nconf == NULL) fatalx("got IMSG_RECONF_DONE but no config"); conf->as = nconf->as; conf->holdtime = nconf->holdtime; conf->bgpid = nconf->bgpid; conf->min_holdtime = nconf->min_holdtime; /* add new peers */ for (p = npeers; p != NULL; p = next) { next = p->next; p->next = peers; peers = p; } /* find ones to be deleted */ for (p = peers; p != NULL; p = p->next) if (p->conf.reconf_action == RECONF_NONE && !p->conf.cloned) p->conf.reconf_action = RECONF_DELETE; /* if there are no new listeners, keep default ones */ if (TAILQ_EMPTY(nconf->listen_addrs)) TAILQ_FOREACH(la, conf->listen_addrs, entry) if (la->flags & DEFAULT_LISTENER) la->reconf = RECONF_KEEP; /* delete old listeners */ for (la = TAILQ_FIRST(conf->listen_addrs); la != NULL; la = nla) { nla = TAILQ_NEXT(la, entry); if (la->reconf == RECONF_NONE) { log_info("not listening on %s any more", log_sockaddr( (struct sockaddr *)&la->sa)); TAILQ_REMOVE(conf->listen_addrs, la, entry); close(la->fd); free(la); } } /* add new listeners */ while ((la = TAILQ_FIRST(nconf->listen_addrs)) != NULL) { TAILQ_REMOVE(nconf->listen_addrs, la, entry); TAILQ_INSERT_TAIL(conf->listen_addrs, la, entry); } setup_listeners(listener_cnt); free(nconf->listen_addrs); free(nconf); nconf = NULL; pending_reconf = 0; log_info("SE reconfigured"); break; case IMSG_MRT_REQ: if ((mrt = calloc(1, sizeof(struct mrt_config))) == NULL) fatal("session_dispatch_imsg"); memcpy(mrt, imsg.data, sizeof(struct mrt_config)); mrt->ibuf = &ibuf_main; LIST_INSERT_HEAD(&mrt_l, mrt, list); break; case IMSG_MRT_END: memcpy(&xmrt, imsg.data, sizeof(struct mrt_config)); LIST_FOREACH(mrt, &mrt_l, list) { if (mrt->type != xmrt.type) continue; if (mrt->peer_id == xmrt.peer_id && mrt->group_id == xmrt.group_id) { LIST_REMOVE(mrt, list); free(mrt); break; } } break; case IMSG_CTL_KROUTE: case IMSG_CTL_KROUTE_ADDR: case IMSG_CTL_SHOW_NEXTHOP: case IMSG_CTL_SHOW_INTERFACE: if (idx != PFD_PIPE_MAIN) fatalx("ctl kroute request not from parent"); control_imsg_relay(&imsg); break; case IMSG_CTL_SHOW_RIB: case IMSG_CTL_SHOW_RIB_PREFIX: case IMSG_CTL_SHOW_NETWORK: if (idx != PFD_PIPE_ROUTE) fatalx("ctl rib request not from RDE"); control_imsg_relay(&imsg); break; case IMSG_CTL_END: control_imsg_relay(&imsg); break; case IMSG_UPDATE: if (idx != PFD_PIPE_ROUTE) fatalx("update request not from RDE"); if (imsg.hdr.len > IMSG_HEADER_SIZE + MAX_PKTSIZE - MSGSIZE_HEADER || imsg.hdr.len < IMSG_HEADER_SIZE + MSGSIZE_UPDATE_MIN - MSGSIZE_HEADER) log_warnx("RDE sent invalid update"); else session_update(imsg.hdr.peerid, imsg.data, imsg.hdr.len - IMSG_HEADER_SIZE); break; case IMSG_UPDATE_ERR: if (idx != PFD_PIPE_ROUTE) fatalx("update request not from RDE"); if (imsg.hdr.len < IMSG_HEADER_SIZE + 2) { log_warnx("RDE sent invalid notification"); break; } if ((p = getpeerbyid(imsg.hdr.peerid)) == NULL) { log_warnx("no such peer: id=%u", imsg.hdr.peerid); break; } data = imsg.data; errcode = *data++; subcode = *data++; if (imsg.hdr.len == IMSG_HEADER_SIZE + 2) data = NULL; session_notification(p, errcode, subcode, data, imsg.hdr.len - IMSG_HEADER_SIZE - 2); break; default: break; } imsg_free(&imsg); } } int la_cmp(struct listen_addr *a, struct listen_addr *b) { struct sockaddr_in *in_a, *in_b; struct sockaddr_in6 *in6_a, *in6_b; if (a->sa.ss_family != b->sa.ss_family) return (1); switch (a->sa.ss_family) { case AF_INET: in_a = (struct sockaddr_in *)&a->sa; in_b = (struct sockaddr_in *)&b->sa; if (in_a->sin_addr.s_addr != in_b->sin_addr.s_addr) return (1); if (in_a->sin_port != in_b->sin_port) return (1); break; case AF_INET6: in6_a = (struct sockaddr_in6 *)&a->sa; in6_b = (struct sockaddr_in6 *)&b->sa; if (bcmp(&in6_a->sin6_addr, &in6_b->sin6_addr, sizeof(struct in6_addr))) return (1); if (in6_a->sin6_port != in6_b->sin6_port) return (1); break; default: fatal("king bula sez: unknown address family"); /* not reached */ } return (0); } struct peer * getpeerbyaddr(struct bgpd_addr *addr) { struct peer *p; /* we might want a more effective way to find peers by IP */ for (p = peers; p != NULL && memcmp(&p->conf.remote_addr, addr, sizeof(p->conf.remote_addr)); p = p->next) ; /* nothing */ return (p); } struct peer * getpeerbyip(struct sockaddr *ip) { struct peer *p, *newpeer, *loose = NULL; u_int32_t id; /* we might want a more effective way to find peers by IP */ for (p = peers; p != NULL; p = p->next) if (!p->conf.template && p->conf.remote_addr.af == ip->sa_family) { if (p->conf.remote_addr.af == AF_INET && p->conf.remote_addr.v4.s_addr == ((struct sockaddr_in *)ip)->sin_addr.s_addr) return (p); if (p->conf.remote_addr.af == AF_INET6 && !bcmp(&p->conf.remote_addr.v6, &((struct sockaddr_in6 *)ip)->sin6_addr, sizeof(p->conf.remote_addr.v6))) return (p); } /* try template matching */ for (p = peers; p != NULL; p = p->next) if (p->conf.template && p->conf.remote_addr.af == ip->sa_family && session_match_mask(p, ip)) if (loose == NULL || loose->conf.remote_masklen < p->conf.remote_masklen) loose = p; if (loose != NULL) { /* clone */ if ((newpeer = malloc(sizeof(struct peer))) == NULL) fatal(NULL); memcpy(newpeer, loose, sizeof(struct peer)); for (id = UINT_MAX; id > UINT_MAX / 2; id--) { for (p = peers; p != NULL && p->conf.id != id; p = p->next) ; /* nothing */ if (p == NULL) { /* we found a free id */ newpeer->conf.id = id; break; } } if (newpeer->conf.remote_addr.af == AF_INET) { newpeer->conf.remote_addr.v4.s_addr = ((struct sockaddr_in *)ip)->sin_addr.s_addr; newpeer->conf.remote_masklen = 32; } if (newpeer->conf.remote_addr.af == AF_INET6) { memcpy(&p->conf.remote_addr.v6, &((struct sockaddr_in6 *)ip)->sin6_addr, sizeof(newpeer->conf.remote_addr.v6)); newpeer->conf.remote_masklen = 128; } newpeer->conf.template = 0; newpeer->conf.cloned = 1; newpeer->state = STATE_NONE; newpeer->rbuf = NULL; init_peer(newpeer); bgp_fsm(newpeer, EVNT_START); newpeer->next = peers; peers = newpeer; return (newpeer); } return (NULL); } int session_match_mask(struct peer *p, struct sockaddr *ip) { int i; in_addr_t v4mask; struct in6_addr *in; struct in6_addr mask; if (p->conf.remote_addr.af == AF_INET) { v4mask = htonl(0xffffffff << (32 - p->conf.remote_masklen)); if (p->conf.remote_addr.v4.s_addr == ((((struct sockaddr_in *)ip)->sin_addr.s_addr) & v4mask)) return (1); else return (0); } if (p->conf.remote_addr.af == AF_INET6) { for (i = 0; i < p->conf.remote_masklen / 8; i++) mask.s6_addr[i] = 0xff; i = p->conf.remote_masklen % 8; if (i) mask.s6_addr[p->conf.remote_masklen / 8] = 0xff00 >> i; in = &((struct sockaddr_in6 *)ip)->sin6_addr; for (i = 0; i < 16; i++) if ((in->s6_addr[i] & mask.s6_addr[i]) != p->conf.remote_addr.addr8[i]) return (0); return (1); } return (0); } struct peer * getpeerbyid(u_int32_t peerid) { struct peer *p; /* we might want a more effective way to find peers by IP */ for (p = peers; p != NULL && p->conf.id != peerid; p = p->next) ; /* nothing */ return (p); } void session_down(struct peer *peer) { peer->stats.last_updown = time(NULL); if (imsg_compose(&ibuf_rde, IMSG_SESSION_DOWN, peer->conf.id, NULL, 0) == -1) fatalx("imsg_compose error"); } void session_up(struct peer *peer) { struct session_up sup; sup.remote_bgpid = peer->remote_bgpid; switch (peer->sa_local.ss_family) { case AF_INET: sup.local_addr.af = AF_INET; memcpy(&sup.local_addr.v4, &((struct sockaddr_in *)&peer->sa_local)->sin_addr, sizeof(sup.local_addr.v4)); sup.remote_addr.af = AF_INET; memcpy(&sup.remote_addr.v4, &((struct sockaddr_in *)&peer->sa_remote)->sin_addr, sizeof(sup.remote_addr.v4)); break; case AF_INET6: sup.local_addr.af = AF_INET6; memcpy(&sup.local_addr.v6, &((struct sockaddr_in6 *)&peer->sa_local)->sin6_addr, sizeof(sup.local_addr.v6)); sup.remote_addr.af = AF_INET6; memcpy(&sup.remote_addr.v6, &((struct sockaddr_in6 *)&peer->sa_remote)->sin6_addr, sizeof(sup.remote_addr.v6)); break; default: fatalx("session_up: unsupported address family"); } memcpy(&sup.conf, &peer->conf, sizeof(sup.conf)); peer->stats.last_updown = time(NULL); if (imsg_compose(&ibuf_rde, IMSG_SESSION_UP, peer->conf.id, &sup, sizeof(sup)) == -1) fatalx("imsg_compose error"); } int imsg_compose_parent(int type, pid_t pid, void *data, u_int16_t datalen) { return (imsg_compose_pid(&ibuf_main, type, pid, data, datalen)); } int imsg_compose_rde(int type, pid_t pid, void *data, u_int16_t datalen) { return (imsg_compose_pid(&ibuf_rde, type, pid, data, datalen)); } static struct sockaddr * addr2sa(struct bgpd_addr *addr, u_int16_t port) { static struct sockaddr_storage ss; struct sockaddr_in *sa_in = (struct sockaddr_in *)&ss; struct sockaddr_in6 *sa_in6 = (struct sockaddr_in6 *)&ss; bzero(&ss, sizeof(ss)); switch (addr->af) { case AF_INET: sa_in->sin_family = AF_INET; sa_in->sin_len = sizeof(struct sockaddr_in); sa_in->sin_addr.s_addr = addr->v4.s_addr; sa_in->sin_port = htons(port); break; case AF_INET6: sa_in6->sin6_family = AF_INET6; sa_in6->sin6_len = sizeof(struct sockaddr_in6); memcpy(&sa_in6->sin6_addr, &addr->v6, sizeof(sa_in6->sin6_addr)); sa_in6->sin6_port = htons(port); break; } return ((struct sockaddr *)&ss); }